# Functions
ChangeRegionInfo used for test handling region info change.
IsLocalStore checks whether a storage is local or not.
MvccDecode parses the origin key and version of an encoded key, if the encoded key is a meta key, just returns the origin key.
MvccEncodeVersionKey returns the encoded key.
# Variables
ErrDBClosed is the error meaning db is closed and we can use it anymore.
ErrInvalidEncodedKey describes parsing an invalid format of EncodedKey.
ErrOverflow is the error returned by CurrentVersion, it describes if there're too many versions allocations in a very short period of time, ID may conflict.
MockRemoteStore mocks remote store.
# Structs
Driver implements kv.Driver interface.
LocalVersionProvider uses local timestamp for version.